U.S. patent number 8,007,316 [Application Number 12/493,898] was granted by the patent office on 2011-08-30 for contact assembly having an integrally formed capacitive element.
This patent grant is currently assigned to Tyco Electronics Corporation. Invention is credited to Brian Patrick Costello.
United States Patent |
8,007,316 |
Costello |
August 30, 2011 |
Contact assembly having an integrally formed capacitive element
Abstract
A contact assembly includes a conductive body, a dielectric
layer and a conductive layer. The conductive body extends along a
longitudinal axis between a mating end and a mounting end. The
dielectric layer is disposed over the conductive body between the
mating end and the mounting end. The conductive layer is disposed
over the dielectric layer and is separated from the conductive body
by the dielectric layer. The conductive layer, the dielectric
layer, and the conductive body form a capacitive element.
Inventors: |
Costello; Brian Patrick (Scotts
Valley, CA) |
Assignee: |
Tyco Electronics Corporation
(Berwyn, PA)
|
Family
ID: |
43381242 |
Appl.
No.: |
12/493,898 |
Filed: |
June 29, 2009 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
|
US 20100330851 A1 |
Dec 30, 2010 |
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Current U.S.
Class: |
439/607.1;
439/620.09 |
Current CPC
Class: |
H01R
13/113 (20130101); H01R 13/04 (20130101); H01R
12/712 (20130101); H01R 13/658 (20130101); H01R
13/7195 (20130101) |
Current International
Class: |
H01R
13/648 (20060101) |
Field of
Search: |
;439/607.1,607.06,607.11 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Vu; Hien
Claims
What is claimed is:
1. A contact assembly of a first connector, the contact assembly
comprising: a conductive body extending along a longitudinal axis
between a mating end and a mounting end; a first dielectric layer
disposed over the conductive body between the mating end and the
mounting end; and a first conductive layer disposed over the first
dielectric layer and separated from the conductive body by the
first dielectric layer, wherein the first conductive layer, the
first dielectric layer, and the conductive body form a capacitive
element, wherein the capacitive element is configured to mate with
a mating contact of a second connector to establish a signal
propagation path that extends from the second connector and through
the first conductive layer, the first dielectric layer, and the
conductive body to the first connector, and wherein the conductive
body, the first dielectric layer, and the first conductive layer
form a contact pin that is receivable into the mating contact of
the second connector.
2. The contact assembly of claim 1, wherein the conductive body,
the first dielectric layer and the first conductive layer form a
capacitive filter.
3. The contact assembly of claim 1, wherein the capacitive element
is in series with the signal propagation path that extends through
the contact assembly.
4. The contact assembly of claim 1, further comprising a second
dielectric layer and a second conductive layer, the second
dielectric layer disposed adjacent to the first conductive layer
and the second conductive layer disposed adjacent to the second
dielectric layer, wherein the signal propagation path extends
through the first and second dielectric layers, the first and
second conductive layers, and the conductive body.
5. The contact assembly of claim 1, wherein the conductive body is
a planar body having opposite faces, further wherein the first
dielectric layer and the first conductive layer are disposed on
each of the opposite faces.
6. The contact assembly of claim 5, wherein the first conductive
layer on each of the opposite faces is configured to engage the
mating contact of a the second connector.
7. The contact assembly of claim 1, wherein the first dielectric
layer has a thickness dimension that is less than a thickness
dimension of each of the first conductive layer and the conductive
body.
8. The contact assembly of claim 1, wherein the conductive body is
a unitary body.
9. The contact assembly of claim 1, wherein the conductive body is
a stamped and formed contact.
10. The contact assembly of claim 1, wherein the signal propagation
path that extends between the first and second connectors through
the first conductive layer, the first dielectric layer, and the
conductive body conveys data signals between the first and second
connectors.
11. The contact assembly of claim 1, wherein the first conductive
layer is not conductively coupled with a ground reference and the
conductive body is not conductively coupled with the ground
reference.
12. A contact assembly of a first connector, the contact assembly
comprising: a planar conductive body extending between opposite
ends, the conductive body including opposite faces; a first
dielectric layer disposed over one or more of the faces of the
conductive body; and a first conductive layer disposed over the
first dielectric layer that is disposed over one or more of the
faces of the conductive body, the first conductive layer separated
from the conductive body by the first dielectric layer and
configured to engage a mating contact of a second connector to
provide a signal propagation path that extends from the second
connector and through the first conductive layer, the first
dielectric layer, and the conductive body to the first connector,
wherein the conductive layer, the dielectric layer, and the
conductive body form a capacitive element, wherein the conductive
body, the first dielectric layer, and the first conductive layer
form a contact pin that is receivable into the mating contact of
the second connector.
13. The contact assembly of claim 12, wherein the conductive body,
the first dielectric layer and the first conductive layer form a
capacitive filter.
14. The contact assembly of claim 12, wherein the conductive body
includes a mounting end for mounting the conductive body to at
least one of a housing connector or a circuit board, further
wherein the conductive body, the first dielectric layer, and the
first conductive layer provide a signal propagation path between
the mating contact and the at least one of the housing connector or
the circuit board.
15. The contact assembly of claim 12, further wherein the
capacitive element is in series with the signal propagation
path.
16. The contact assembly of claim 12, further comprising a second
dielectric layer and a second conductive layer, the second
dielectric layer disposed adjacent to the first conductive layer
and the second conductive layer disposed adjacent to the second
dielectric layer, wherein the signal propagation path extends
through the first and second dielectric layers, the first and
second conductive layers, and the conductive body.
17. The contact assembly of claim 12, wherein the first dielectric
layer has a thickness dimension that is less than a thickness
dimension of each of the first conductive layer and the conductive
body.
18. The contact assembly of claim 12, wherein the conductive body
is a unitary body.
19. The contact assembly of claim 12, wherein the conductive body
is a stamped and formed contact.
20. The contact assembly of claim 12, wherein the first dielectric
layer forms a dielectric coating that substantially surrounds at
least one of the ends of the conductive body.
21. The contact assembly of claim 12, wherein the signal
propagation path that extends between the first and second
connectors through the first conductive layer, the first dielectric
layer, and the conductive body conveys data signals between the
first and second connectors.
22. The contact assembly of claim 12, wherein the first conductive
layer is not conductively coupled with a ground reference and the
conductive body is not conductively coupled with the ground
reference.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to contacts used in electrical
connectors and, more particularly, to contacts used in conjunction
with capacitive filters.
Known electrical connectors are capable of communicating data
signals at relatively high rates. The signals are communicated
between a connector and another connector and/or a circuit board
via one or more contacts. Electrical noise in the signals may
increase as the speed at which the signals are communicated
increases. In some known connectors, one or more capacitive filters
are provided to filter out noise from the signals. For example,
some known connectors include one or more capacitors provided in
series with contacts to filter out noise in the signals
communicated through the contacts. The capacitive filter may be
disposed on the circuit board to which the connector is mounted.
One or more conductive traces in the circuit board electrically
couple the contacts with the capacitive filter. Signals
communicated by the connector propagate through the contacts and
the capacitive filter via the conductive traces.
Communicating signals through the conductive traces and the
capacitive filter increases the total path over which the signals
propagate. For example, directing the signals from the contacts and
through conductive traces and a capacitive filter before
communicating the signals to a final destination adds to the total
length over which the signals travel before reaching the
destination. Increasing the total length over which the signals
travel, that is, the signal path length, may increase the time
delay skew in signals communicated through the contacts and
capacitive filter. For example, in a connector that communicates
differential pair signals over at least two contacts, the
additional signal path length that is required to direct the
signals through the capacitive filter may increase the time delay
skew between the signals.
Additionally, communicating signals through the conductive traces
and the capacitive filter may consume more of the already limited
real estate on a circuit board. For example, a relatively large
number of conductive traces and capacitive filters may be required
in a circuit board in order to filter signals communicated using
connectors that have several contacts. The large number of
conductive traces and capacitive filters may consume a relatively
large amount of available area of the circuit board to which the
connector is mounted and prevent this area from being used for
other connectors or components.
Another drawback for circuit board-mounted capacitors and other
components is the need for vias in the circuit board. The vias may
include small plated through holes in the circuit board that carry
signals between the capacitors or components and conductive traces
in the circuit board. For example, vias may carry signals from
inside a controlled impedance layer of the circuit board up to the
surface of the circuit board, and then back down again into the
circuit board. Such a signal propagation path through the circuit
board adds discontinuity to the propagation path and may cause
signal degradation.
Thus, a need exists for a contact assembly that communicates and
filters signals, while minimizing any increases to the signal
length, reducing the amount of area that is used on a circuit board
to communicate and filter the signals, and/or decreasing
discontinuities in signal propagation paths through the circuit
board.
BRIEF DESCRIPTION OF THE INVENTION
In one embodiment, a contact assembly is provided. The assembly
includes a conductive body, a dielectric layer and a conductive
layer. The conductive body extends along a longitudinal axis
between a mating end and a mounting end. The dielectric layer is
disposed over the conductive body between the mating end and the
mounting end. The conductive layer is disposed over the dielectric
layer and is separated from the conductive body by the dielectric
layer. The conductive layer, the dielectric layer, and the
conductive body form a capacitive element. Optionally, the
conductive body, the dielectric layer and the conductive layer may
form a capacitive filter. In one embodiment, the conductive body
provides a signal propagation path between the mating connector and
the at least one of the housing connector and the circuit board.
The capacitive element may be in series with the signal propagation
path.
In another embodiment, another contact assembly is provided. The
assembly includes a conductive body, a dielectric layer and a
conductive layer. The conductive body is a planar body that extends
between opposite ends and includes opposite faces. The dielectric
layer is disposed over the faces of the conductive body. The
conductive layer is disposed over the faces of the conductive body
and over the dielectric layer. The conductive layer is separated
from the conductive body by the dielectric layer and is configured
to engage a mating contact to provide a signal propagation path
between the mating contact and the conductive body. The conductive
layer, the dielectric layer, and the conductive body form a
capacitive element.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a connector system in accordance
with one embodiment.
FIG. 2 is an elevational view of a contact assembly shown in FIG. 1
in accordance with one embodiment.
FIG. 3 is a cross-sectional view of the contact assembly shown in
FIG. 1 and a receptacle contact in accordance with one
embodiment.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view of a connector system 100 in
accordance with one embodiment. The connector system 100 includes
two connectors 102, 104 that mate with one another to electrically
couple two circuit boards 106, 108. For example, a right angle
mating connector 102 is mounted to the circuit board 106 while a
mounted connector 104 is mounted to the circuit board 108. The
mounted connector 104 includes several contact assemblies 110 that
mate with receptacle contacts 300 (shown in FIG. 3) of the mating
connector 102 to electrically join the connectors 102, 104. One or
more embodiments of the contact assemblies 110 that are described
herein may be used with connectors or devices other than those
shown in the attached figures. For example, one or more embodiments
of the contact assemblies 110 may be used in a system or device
having two or more electrical components mated with another to
establish a signal propagation path through at least a portion of
the two mated components, where a capacitive element is provided in
series with the signal propagation path to provide a capacitive
filter.
FIG. 2 is an elevational view of the contact assembly 110 in
accordance with one embodiment. In the illustrated embodiment, the
contact assembly 110 is a contact pin that is received into another
contact. Alternatively, the contact assembly 110 may be a
receptacle contact that receives another contact. The contact
assembly 110 is elongated along a longitudinal axis 200 between a
mating end 202 and a mounting end 204. The mating end 202 is
received in the receptacle contact 300 (shown in FIG. 3) of the
mating connector 102. The mounting end 204 is mounted to the
circuit board 108 (shown in FIG. 1). In the illustrated embodiment,
the mounting end 204 includes a compliant eye-of-needle (EON) pin
220 that is received in a cavity (not shown) of the circuit board
108 to secure the contact assembly 110 to the circuit board
108.
The contact assembly 110 is a substantially planar body having
opposite faces 206, 208 in the illustrated embodiment.
Alternatively, the contact assembly 110 may have a different shape.
Each of the faces 206, 208 extends over a surface area 218 that has
a width dimension 210 and a height dimension 212. The surface area
218 also may include the surface area of shoulders 214, 216 that
extend laterally from the longitudinal axis 200 of the contact
assembly 110 at or near the mounting end 204. In one embodiment,
the surface area 218 of each face 206, 208 may be approximated by
multiplying the width dimension 210 by the height dimension 212.
The surface area 218 may represent the area of the contact assembly
110 over which data signals are communicated through the contact
assembly 110.
FIG. 3 is a cross-sectional view of the contact assembly 110 and
the receptacle contact 300 in accordance with one embodiment. The
receptacle contact 300 is held by or in the mating connector 102
(shown in FIG. 1). The receptacle contact 300 includes opposing
arms 302, 304. The receptacle contact 300 is formed of, or
includes, a conductive material, such as a metal or metal alloy.
The contact assembly 110 is loaded between the arms 302, 304 to
mate and electrically couple the receptacle contact 300 with the
contact assembly 110. The mating of the contact assembly 110 and
receptacle contact 300 establishes a signal propagation path 306
that extends through at least a portion of each of the contact
assembly 110 and the receptacle contact 300. The signal propagation
path 306 is schematically illustrated in FIG. 3 and may differ or
deviate from the embodiment shown in FIG. 3. The mating connector
102 (shown in FIG. 1) and mounting connector 104 (shown in FIG. 1)
may communicate data signals along the signal propagation path 306
between one another.
The contact assembly 110 includes one or more dielectric layers 310
that are sandwiched between conductive bodies or layers. For
example, the contact assembly 110 may include a dielectric layer
310 that is between a conductive body 308 and one or more
conductive layers 318. The conductive body 308 extends between the
mating end 202 and the mounting end 204 along the longitudinal axis
200. The conductive body 308 includes, or is formed from, a
conductive material, such as a metal or metal alloy. In one
embodiment, the conductive body 308 is formed from a copper alloy.
The conductive body 308 is a unitary body in one embodiment. For
example, the conductive body 308 may be stamped and formed from a
sheet of conductive material. Alternatively, the conductive body
308 may be a molded body. The conductive body 308 provides part of
the signal propagation path 306. For example, signals may be
communicated between the mating connector 102 (shown in FIG. 1) and
the circuit board 108 (shown in FIG. 1) via the conductive body
308.
The contact assembly 110 also includes a dielectric layer 310 over
the conductive body 308. The dielectric layer 310 extends over at
least a portion of the length of the conductive body 308 between
the mating end 202 and the mounting end 204. For example, the
dielectric layer 310 may be deposited over the surface area 218
(shown in FIG. 2) of the conductive body 308. In one embodiment,
the dielectric layer 310 substantially encloses or surrounds the
conductive body 308 between the mating end 202 and the mounting end
204. For example, the conductive body 308 may be coated with the
dielectric layer 310 around all or substantially all of the
conductive body 308. Alternatively, only a portion of the
conductive body 308 is enclosed by the dielectric layer 310. For
example, the conductive body 308 may be coated by the dielectric
layer 310 from the mating end 202 to a location above the EON pin
at the mounting end 204. The dielectric layer 310 may be applied
over just the opposite faces 206, 208 of the conductive body 308.
For example, the dielectric layer 310 may be deposited only on the
faces 206, 208 and not over the mating end 202.
The dielectric layer 310 includes or is formed from, one or more
nonconductive or electrically insulative materials. The dielectric
layer 310 may include, or be formed from, materials that have a
relatively large dielectric constant (.di-elect cons.). For
example, the dielectric layer 310 may have a dielectric constant or
relative static permittivity (.di-elect cons.) of about 80 to 150
Farads per meter. In one embodiment, the dielectric layer 310
includes, or is formed from, barium titanate (BaTiO.sub.3).
Alternatively, the dielectric layer 310 includes, or is formed
from, tantalum pentoxide or tantalum oxide (Ta.sub.2O.sub.5).
The dielectric layer 310 is provided over the conductive body 308
at a relatively small thickness. For example, the dielectric layer
310 may be deposited in a thickness dimension 312 that is less than
a thickness dimension 314 of the conductive body 308 and less than
a thickness dimension 316 of one or more of the conductive layers
318. By way of example only, the dielectric layer 310 may be
deposited directly onto the conductive body 308 on each of the
faces 206, 208 of the conductive body 308 at a thickness dimension
312 of approximately 5 microns or less. As another nonlimiting
example, the dielectric layer 310 may be deposited at a thickness
dimension 312 of approximately 100 nanometers to approximately 10
microns.
The dielectric layer 310 may be provided over the conductive body
308 by any of a variety of deposition techniques and processes. By
way of example only, the dielectric layer 310 may be deposited
directly onto the conductive body 308, such as by sputtering the
dielectric layer 310 onto the conductive body 308. In another
example, the dielectric layer 310 may be deposited onto the
conductive body 308 by electrocoating the conductive body 308 with
the dielectric layer 310. Alternatively, the dielectric layer 310
may be provided as an adhesive film or tape that is adhered to the
exterior surface of the conductive body 308. For example, a tape
that includes the dielectric layer 310 may be adhered to the
opposite faces 206, 208 of the conductive body 308.
The conductive layer 318 is disposed over the dielectric layer 310.
For example, the conductive layer 318 may be deposited onto, or
adjacent to, the exterior surface of the dielectric layer 310. The
conductive layer 318 is provided above the dielectric layer 310
such that the conductive layer 318 does not directly contact the
conductive body 308. For example, the dielectric layer 310 may
separate the conductive layer 318 from the conductive body 308 such
that there is no direct electrical continuity path extending
directly from the conductive layer 318 to the conductive body 308.
The conductive layer 318 extends over at least a portion of the
length of the dielectric layer 310 and the conductive body 308
between the mating end 202 and the mounting end 204. For example,
the conductive layer 318 may be deposited over the surface area 218
(shown in FIG. 2) of the dielectric layer 310 and the conductive
body 308. In the illustrated embodiment, the conductive layer 318
is provided as separate layers on opposite sides of the dielectric
layer 310. For example, the conductive layer 318 is shown in FIG. 3
as including a layer deposited above the dielectric layer 310 above
each of the faces 206, 208 of the conductive body 308. The
conductive layer 318 extends between opposite outer ends 320, 322
above each face 206, 208. The outer ends 320 of the conductive
layer 318 are located at or near the mating end 202. The outer ends
322 are disposed above the shoulders 214, 216 in the illustrated
embodiment. Alternatively, the conductive layer 318 is provided
above the dielectric layer 310 such that the conductive layer 318
substantially encloses or surrounds the dielectric layer 310. For
example the dielectric layer 310 may be coated with the conductive
layer 318 around all or substantially all of the dielectric layer
310.
The conductive layer 318 includes or is formed from, one or more
conductive materials. By way of example only, the conductive layer
318 may be a copper alloy that is at least partially plated with
gold. Alternatively, a different metal or other conductive material
may be used as the conductive layer 318. The conductive layer 318
is deposited at the thickness dimension 316 above the dielectric
layer 310. The thickness dimension 316 of the conductive layer 318
may be larger than the thickness dimension 312 of the dielectric
layer 310 and smaller than the thickness dimension 314 of the
conductive body 308. The conductive layer 318 may be provided by
any of a variety of deposition techniques and processes. By way of
example only, the conductive layer 318 may be deposited directly
onto the dielectric layer 310 by sputtering the conductive layer
318 onto the dielectric layer 310. In another example, the
conductive layer 318 may be deposited by electroplating the
conductive layer 318 onto the dielectric layer 310. Alternatively,
the conductive layer 318 may be provided as a conductive film or
tape that is adhered to the exterior surface of the dielectric
layer 310.
In another embodiment, the dielectric layer 310 and the conductive
layer 318 are provided above the conductive body 308 prior to
stamping and forming the contact assembly 110. For example, the
dielectric layer 310 and the conductive layer 318 may be deposited
on the opposite sides of a conductive sheet. The conductive sheet,
the dielectric layers 310 and the conductive layers 318 may be
stamped and formed from the conductive sheet to form the contact
assembly 110. In such an example, the conductive sheet is stamped
and formed into the conductive body 308 shown in FIG. 3.
The conductive body 308, the dielectric layer 310 and the
conductive layer 318 form a capacitive element. For example, the
dielectric layer 310 separates the conductive body 308 and the
conductive layer 318 from one another to form a capacitor. The
capacitive element created by the conductive body 308, the
dielectric layer 310 and the conductive layer 318 may be a
capacitive filter that is integrally formed with the contact
assembly 110. For example, the contact assembly 110 shown in FIG. 3
is formed so as to have an inherent electrical capacitive
characteristic (C). The contact assembly 110 and capacitive filter
formed by the contact assembly 110 may be provided as a unitary
body, rather than a capacitive filter that is external to the
contact assembly 110 and electrically coupled thereto.
The capacitive element that is formed by the contact assembly 110
is disposed in series with the signal propagation path 306 in the
illustrated embodiment. As shown in FIG. 3, the receptacle contact
300 engages the conductive layer 318 of the contact assembly 110
above the opposite faces 206, 208 to electrically couple the
receptacle contact 300 and the contact assembly 110. Data signals
may be communicated between the receptacle contact 300 and the
contact assembly 110 along the signal propagation path 306 such
that the signals pass through the capacitive element formed by the
contact assembly 110. For example, a data signal that is
communicated from the receptacle contact 300 to the contact
assembly 110 passes through the arms 302, 304 of the receptacle
contact 300 to the conductive layer 318, from the conductive layer
318 to the conductive body 308 by passing across the dielectric
layer 310, and from the conductive body 308 to the circuit board
108 (shown in FIG. 1) to which the contact assembly 110 is
mounted.
The signals may be filtered by the capacitive element formed by the
contact assembly 110. The inherent capacitive properties of the
contact assembly 110 permit the contact assembly 110 to both
communicate signals and to filter the signals. The contact assembly
110 may filter out noise from relatively high speed signals that
are communicated along the signal propagation path 306. By way of
example only, the capacitive element may be a high pass filter that
filters out signals communicated at a frequency below a cutoff
frequency of the contact assembly 110. The contact assembly 110 may
permit the signals communicated at frequencies above the cutoff
frequency to be communicated along the signal propagation path 306
while preventing signals transmitted at lower frequencies to pass
along the signal propagation path 306. In another example, the
capacitive element may be a low pass filter that filters out
signals communicated at a frequency above a cutoff frequency of the
contact assembly 110. The contact assembly 110 may permit the
signals communicated at frequencies below the cutoff frequency to
be communicated along the signal propagation path 306 while
preventing signals transmitted at higher frequencies to pass along
the signal propagation path 306. As the capacitive element is
integrally formed with the contact assembly 110, the contact
assembly 110 may effectively include a capacitive filter without
significantly increasing the signal length over which the signals
travel along the signal propagation path 306. Therefore, the
contact assembly 110 may both communicate and filter signals
without significantly impacting the time delay skew in the
signals.
An electrical capacitance characteristic (C) of the contact
assembly 110 represents an ability of the contact assembly 110 to
hold an electric charge. The capacitance characteristic (C) of the
contact assembly 110 may be based on a relation with the surface
area 218 (shown in FIG. 2) of faces 206, 208 of the contact
assembly 110 and the thickness dimension 312 of the dielectric
layer 310. For example, the electrical capacitance characteristic
(C) of the contact assembly 110 may be based on the relation:
.times. ##EQU00001## where C represents the electrical capacitance
characteristic of the contact assembly 110, .di-elect cons.
represents the dielectric constant of the dielectric layer 310, A
represents the surface area of the contact assembly 110 over which
the electric potential of signals communicated through the contact
assembly 110 extends, and d represents the thickness dimension 312
of the dielectric layer 310. In the embodiment illustrated in FIG.
3, the surface area A of Equation 1 includes the total surface area
over which signals are communicated through the contact assembly
110. For example, the surface area A may include the sum total of
the surface area 218 of the face 206 and the surface area 218 of
the face 208 of the contact assembly 110. As shown in Equation 1,
as the surface area 218 of the faces 206, 208 increases and/or the
thickness dimension 312 of the dielectric layer 310 decreases, the
electrical capacitance characteristic (C) of the contact assembly
110 may increase. In another example, increasing the dielectric
constant (.di-elect cons.) by changing the material or materials
included in the dielectric layer 310 also can increase the electric
capacitance characteristic (C) of the contact assembly 110.
The electrical capacitance characteristic (C) of the contact
assembly 110 may be increased by providing additional dielectric
layers 310 and additional conductive layers 318. For example, a
second dielectric layer that is similar to the dielectric layer 310
may be deposited onto the conductive layer 318 and a second
conductive layer that is similar to the conductive layer 318 may be
deposited onto the second dielectric layer. In another example,
several additional dielectric layers and conductive layers may be
alternatively deposited on one another to form a multi-layer
structure on the conductive body 308 to form several capacitive
elements integrally formed with the contact assembly 110.
Dimensions, types of materials, orientations of the various
components, and the number and positions of the various components
described herein are intended to define parameters of certain
embodiments, and are by no means limiting and are merely exemplary
embodiments. Many other embodiments and modifications within the
spirit and scope of the claims will be apparent to those of skill
in the art upon reviewing the above description. The scope of the
invention should, therefore, be determined with reference to the
appended claims, along with the full scope of equivalents to which
such claims are entitled. In the appended claims, the terms
"including" and "in which" are used as the plain-English
equivalents of the respective terms "comprising" and "wherein."
Moreover, in the following claims, the terms "first," "second," and
"third," etc. are used merely as labels, and are not intended to
impose numerical requirements on their objects. Further, the
limitations of the following claims are not written in
means-plus-function format and are not intended to be interpreted
based on 35 U.S.C. .sctn.1102, sixth paragraph, unless and until
such claim limitations expressly use the phrase "means for"
followed by a statement of function void of further structure.
* * * * *